Solar panels are generally well known (see, e.g., U.S. Pub. No. 2006/0283497 (Hines) and U.S. Pub. No. 2010/0018570 (Cashion et al.)). Installing a system of solar panels on a rooftop can present a number of logistical challenges.
One challenge is to create a structure that will hold the panels in place on the rooftop given wind, seismic and roof weight capacity requirements. Many systems are presently available in the market and there are many years of industry experience, specifically with traditional flat plate solar panels. Traditional rooftop mounting structures are typically shipped to the job site in pieces and generally installed on the roof before solar panels arrive. FIG. 1 shows an installation of concentrating photovoltaic (CPV) panels with such traditional racking practices. As shown, three panels 10, 20, and 30 are mounted on a roof 50. Each of the panels 10, 20, and 30 includes six concentrating photovoltaic modules 15. Also, the panels 10, 20, and 30 are mounted to the roof 50 using racking system 40.
Racking system 40 includes two mounting rails 41 positioned on round cross rails 43. The round cross rails are supported above the surface of roof 50 via posts 42. Each of the panels 10, 20, and 30 are coupled to rails 41.
Another challenge can be to merely get the product and balance of system from the factory to the rooftop in an efficient manner. One traditional approach with flat panels is to palletize the solar panels in a box roughly 48″ cube and fill a container and take it to the job site to be craned to the roof. Another method used by some, to save on expensive rooftop labor, is to build an array of multiple solar panels into one large framework. These are then delivered to a jobsite on an open flatbed truck and craned directly to the roof as shown in FIG. 2. As shown, a group 60 having six panel arrays 61 can be lifted to a roof via crane 64. Each array 61 includes four traditional flat solar panels 62. Panels 62 are held together in each respective array 61 via steel beams 63 that run lengthwise on an outer edge of the panels 62. The steel beams 63 become part of the racking system (not shown).
Concentrating photovoltaic (CPV) panels are generally bigger and bulkier than flat plate solar panels. This is because they typically require some distance in order to focus the light onto solar cells. This can be a bigger logistical challenge to ship product to jobsites. More specifically, flat plate solar panels can be stacked on each other in a compact manner while CPV panels generally cannot. This is true because CPV panels typically track the sun in two axes and generally have a shape somewhat complicated and non-conducive to stacking.
One approach is to create a box or packaging that can be used to ship product in a container 70, as shown in FIG. 3. As shown, container 70 is partially filled with concentrating photovoltaic panels 71 that are mounted in four racking systems 73 that are designed to be reusable for transporting panels 71. Each concentrating photovoltaic panel 71 includes six concentrating photovoltaic modules 77 connected to one tracker 78. However, a panel could include seven, eight, or any number of modules 77. The racking system 73 is wide enough to contain two panels 71 and has a height to accommodate two panels 71 stacked on two additional panels (as shown it the middle racking system 73). The racking system towards the front has room to accommodate two additional modules 77 that could be stacked on the bottom two modules 77 (as shown in the middle racking system 73). Racking systems similar to racking system 73 can be wider, e.g., having a width to accommodate three panels 71, which is typical for domestic trailers or flatbed trucks (not shown). Each racking system 73 includes four corner posts 75 and each post 75 has a pointed/rounded top 74 that can mate with the bottom 76 of another post 75 such that racking system 73 can have another racking system 73 be stacked thereon (e.g., as shown in the rear of container 70). Similarly, racking system 73 could be stacked on top of another racking system 73 via the mating portions of posts 75. Posts 75 also include loops 79 that can be used by a crane to lift racking system 73 to a roof (not shown).
This packaging (racking system 73 plus panels 71) can also be craned to the rooftop where the panels 71 are removed from the packaging. The packaging is not used to install the panels to the rooftop. Such a package can be inherently expensive to make so the packaging is typically returned and reused. Being returnable can create a logistic and freight cost issue to stack these at a jobsite and return them. The packaging can be made collapsible to mitigate some of the freight cost. However, it can also create a significant amount of capital investment in the returnable packaging because enough of these are typically made to ensure all jobsites can have them and that the factory never runs out. This could be a supply equal to months of manufacturing capacity.